Split retreated cautiously, clearing the deck herself for action. But no first gun was fired in that engagement. A crackling of the document hidden over the spot where she thought her heart was came like a warning note to Sissy. She struggled against it a moment; then her hands fell. Meekly she turned her back upon her tormentor, and in a voice of such exquisite holiness as to be almost unearthly, she said: "Split dear, will you please button me?" A look of outraged astonishment at the unheard-of endearment came over Irene's face. The Madigans regarded demonstrative affection as pure affectation at its best; at its worst it was little short of indecent. "'Split dear?'" mocked Irene as soon as she recovered. "Yes, dear. Turn around, dear. Stand straight, dear. Wait a minute, dear--" Sissy stood in silence, biting her tongue that she might not speak. She was so occupied with the desire to keep Number 10 of her compact with herself that she did not notice how long it was before Irene really began to button her waist. She did note, though, that she began at the bottom, a proceeding Split fancied merely because it drove her junior nearly frantic. She buttoned with maddening slowness up to the middle, when she capriciously left this point and recommenced at the top. [Illustration: "'That settles Number 10,' said Sissy, grimly"] Mentally Sissy followed the operation. It was almost complete when through the little gap purposely left open Split deftly introduced a providentially flattened piece of ice from the window-sill, giving her victim a little shake that sent the ice slipping smoothly down her squirming body, but escaping before Sissy could turn and rend her. "That settles Number 10," said Sissy, grimly, to herself, while she danced with discomfort. "I'll kill her if I get a chance--that's what I'll do. I'll get even, or my name's not Sis Madigan." She hurried back into her room, which the twins shared, and stood in damp martyrdom while Bessie's butter-fingers crept with miserable slowness up and down. She suffered so from Bessie's ineptness that, despite the requirements of Number 3 of her code, she tore herself violently from her and turned her back imploringly to Florence. But Fom was a partizan of Split's, and it was against all the ethics of Madigan warfare to aid and comfort the enemy. When Sissy, chastened, returned to Bep's ministrations, the blonde one of the twins was so hurt and offended by the implication of awkwardness--a point upon which she was as vulnerable as she was sensitive--that Sissy slapped them both before she went at last for relief to Aunt Anne. This was fatal, as she knew it would be. "I shall tell your father about Irene," her aunt said, looking up from the coffee she was sipping as she lay in bed reading a French book. "But it's just as well, for I told you yesterday that that dress was too dirty to wear another day. Change it now--" "Oh, Aunt Anne, it's late already--"